Merocyanine dyes and process of preparing them



45 such as 4-methyloxazole,4-phenyloxazole, ben- Pa tented Jan. 2,

miaocra DYES AND raocuss o ,rasraamc THEM Leslie G. S. Brooker,Rochester,-N. Y., assignor I to Eastman Kodak Company, Rochester, N.Y.,. a corporation of New Jersey I No Drawing; Application July 15,.1937,

. ,Serial No. 153,817 1 21 Claims. (Cl.- 260257) This inventionrelatesto -dyes and aprocess for preparing the same. The new dyes of myinvention can be called -merocyanine dyes. This application is acontinuation-in-part of my copending' application Serial No. 739,502,filed August 11, 1934.

The new dyes of my instant invention can be formulated as'follows:

and

wherein A represents a divalent non-metallic atom oi the oxygen group ofelements, such as oxygen or sulfur, R represents an alkyl group, Y and Yrepresent the nnmetal1ic atoms necessary to complete a heterocyclicnucleus .devoid of nuclear carbonyl groups, e. gz-oxocarbonyl .(commonlycalled 'carbonyl) and thiocarbonyl' groups, and Z represents thenon-metallic atoms necessary to complete a heterocyclic nucleus. It

is very likely that the new dyes are resonance hybrids between the twoforms which can be illustrated as follows for formula I:

A='Cd=='CN-It AC=d--C=N--R G9 9 More specifically, in the aboveformulasR can represent any alkyl group, such as methyl, ethyl,

, n-butyl, isobutyl, allyl, isopropyl, n-propyl and n-decyl, forexample. Y can represent the nonmetallic atoms necessary to complete afive-- membered heterocyclic nucleus, such as'a thiazole nucleus, forexample. 4-methylthiazole, 4-phenylthiazole. 4,5-diphenylthiazole,benzothiazole or naphthothiazole nuclei. a selenazole nucleus, forexample, 4-methylse'lenazole, 4-phenylselenazole or henzoselenazolenuclei, an .oxazole nucleus,

zoxazoie ornaphthoxazole nuclei, .a thiazoline nucleus,- a-3,3-dialkylindolenine nucleus or a selenazoline nucleus. Y- and Y canrepresent the non-metallic-atoms necessary to complete a sixmemberedheterocyclic nucleus, such as' a pyridine nucleus or a'quinolinenucleus, for example. G-methylquinoline or benzoquinoline; Z canrepresent the non-metallic atoms necessary to complete a flve-memberedheterocyclic nucleus for example, a 2,4,(3, -thiazoledionenucleus, suchas- 2,4(3,5)ethiazoledione, 3-alkyl-2,4(3,5) -thiazoledione,3-phenyl-2,4(3,5) -thiazoledione or 8-' naphthyl-2,4(3,5) -thiazoledionenuclei, a 2--thio- 2,4(3,5) -thiazoledione (a rhodanine) nucleus, suchas 3-alkyl-2-thio-2,4(3,5)-thiazo1edione (3- alkylrhodanine) 3pheny1-2-thlo-2,4(3,5 -thiazoledione (3-phenylrhodanine), 3-naphthyl-2-thio-2,4 3,5) -thiazoledione (3 naphthylrhodanine) nuclei or3-(l-benzothiazyl) -2-'-thio- 2,4(3,5) -thiazoledione(3-(1-benzothiazyl) -rhodanine) nuclei, a 2,4-dithio-2,4(3,5)-thiazoledione (4-thiorhodanlne) nucleus, such as 2,4

dithio-2,4(3,5) thiazoledione or its 3-alkyl, 3- phenyl or 3-naphthylderivatives, a 2-alkylmercapto-4(5) -thiazolone.nucleus, such as2,-ethylmercapto-4(5) -thiazolone, a 2,4(3,5) -thiazoledione nucleus,such as 2,4 (3,5)'-thiazoledione or its 3-alkyl,3-phenyl or 3-naphthylderivatives, a

' thiazolidone nucleus, such as -thlazolidoneor its 3-alkyl, 3-phenyl or3-naphthyl derivatives, a 2-alkylphenylamino-4(5) -thiazolone nucleus,or a Z-diphenylamino-AG) -thiazolone nucleus; an oxazolone nucleus, .forexample, a 2 -thio- 2,4(3,5)- oxazoledione nucelus, such as 3-alkyl-2-thio-2,4(3,5)-oxazo1edione nucleus; an imidazolcne nucleus, forexample, a 2,4(3,5 )-imidazoledione nucleus, such as2,4(3,5)-imidazoledione (hydantoin) or its 3-alkyl, S-phenyl or 3-naphthyl derivatives, as well as its 1,3-dialkyl, 1- alkyl-3-phenyl;1-alkyl-3-naphthyl, 1,3-diphenyl,

etc., derivatives, a 2-thi0-2,4(3,5)Amidazoledione nucleus, such as2-thio-2',4(3,5)-imidazo1edi0ne (Z-thiohydantoin) or its 3-a-lkyl,3-phenyl or 3- nap'hthyl derivatives, as well as its 1,3-dialkyl,l-alkyl-3-phenyl, 1-alkyl-3-naphthyl, 1,3-diphenyl, etc., derivatives, a4-thi0-2,4(3,5) -im idazoledione nucleus such as 4-thio-2,4(3,5)-'imadazoledione (4-thiohydant'oin) or its 3-alkyl,

' 3-phenyl or 8-naphthyl derivatives, as well as its 1,3-dialkyl,'1-alkyl-3-phenyl,

1-alky1-3-naphthyl, 1,3-diphenyl, etc., derivatives, a2-alkylmercame-5(4) -imidazolone, such as 2-propylmercapto-5(4)1-imidazolone; a thionaphthenone nucleus, such as 2-(1)-thionaphthenone or1(2)- thionaphthenone, a pyrazolone nucleus, for example, a5-thiopyrazolone, such as 1-phenyl-3- methyl-5-thiopyrazolone; anoxlndole nucleus, such as 2,3-dihydro-3-ketoindole, and likefivemembered heterocyclic nuclei. Z can also represent thenon-metallicatoms necessary to com plete; a six-membered heterocyclic nucleus, such,as a 2,4,6-triketohexahydropyrimidine nucleus,

for example, barbituric acid or 2-thiobarbituric acid, as well as theirl-alkyl or 1,3-dialkyl derivatives; a 3,4-dihydro-2( 1) -qu inolinenucleus, such as 3,4-dihydro-2(1)-quinoline (dihydrocarbostyril); a3,4-dihydr'o-2(1)-quinoxalone nucleus, such as 3,4-dihydro-2(1)-q1nnoxalone (oxydihy- V droquinoxaline); 3-phenomorpholone(1,4,2-benzoxazine-3(4)-one or benzo-fl-morpholone) nuclei;1,4,2-benzothiazine-3 (4 )-one (ketodihydrobenzoparathiazine) nuclei andthe like six-membered heterocyclic nuclei.

I am aware that indigoid' types of dyes are known and do not intend toembrace that type of dye. My invefit'ion is particularly concerned withorganic bases, particularly strong tertiary organic bases whose aqueoussolutions have dissociation constantssubstantiallygreater than that ofpyridine are advantageously employed. Examples of such strong organicbases are triethyl amine, tributyi amines, N-meth ylpiperidi'ne andtriethanol amine. Other basic condensing agents can be, employed, forexample, sodium carbonate, sodium hydroxide, potassium carbonate orsodium ethylate. The reactions are advantageously effected in thepresence of a diluent, lower aliphatic alcohols, i. e. those of theformula CnHZn+10H wherein n represents 1, 2, 3 or.4, are advantageouslyemployed. Ethyl, isopropyl and n-propyl alcohols are particularlyuseful. Other diluents can 'be employed. Heat accelerates the'formationof my new dyes.

As cyclammonium quaternary salts, I employ any quaternary salt, such,forexample, as corresponds to the heterocyclic nuclei set forth under Y ofthe above formulas and containing a reactive group in the alpha or gammaposition. I

- have found that alkyl halides, particularlyfalk- .LBO

iodides, are advantageously employed. As heterocyclic organiccompounds'containing a nuclear reactive methylene group adjacent to anuclear carbonyl group, I employ any heterocyclic organic compoundcontaining a nuclear reactive methylene group adjacent to a nuclearcarbonyl group, such, for example, as corresponds to the heterocyclicnuclei ,set forth under Z of the above formulas. I have found thatheterocyclic organic compounds containing a nuclear V reactive methylenegroup adjacent to a nuclear oxacarbonyl group are advantageouslyemployed. I have found that ordinarily the cyclammonium quaternary saltand the heterocyclic organic compound can be employed in equimolecularproportions. However, an excess of either can'be employed. The basiccondensing agent is likewise ordinarily employed in an amount suificientto bind the elements of acid eliminated from the condensing molecules,although smaller or larger amountscan \be employed. A small excess, of

condensing agent is ordinarily suitable.

Thedys wherein Z of the above formulas reP-. resents the non-metallicatoms necessary to complete a five-membered heteroeyclic organic nucleushaving a nuclear nitrogen and nuclear sulr fur atom are particularlyuseful in preparing parts of absolute ethyl alcohol for fifteen minutes.

optically sensitized photographic emulsions I have found.

While the process of preparing my new dyes vis subject to variation,particularly as respects the nature and quantity of reactants employed,the nature and quantity'of condensing agent employed, the nature andquantity of diluent employed, the temperature employed, and the methodsof isolation and purification of the dyes, the following examples serveto illustrate the manner of practicing my invention:

Exsurnr: 1. -(1-ethyl-2-quinolylidene)- 'rhodanine 2.66 parts ofrhodanine, as parts of 2-iodoquinoline ethiodide and 4.24 parts oftriethylamine were refluxed in parts of absolute ethyl alcohol for about15 minutes. The dye separated from the hot solution. It was filtered offand recrystallized from glacial acetic acid, giving brownish red needleswith a green reflex. The methyl alcoholsolution was orange in color.

EXAMPLE 2.5(l-ethyl-z-quinolylidene) -3- phenylrhodanine 2.1 parts of3-phenylrhodanine and 4.1 parts of 2-iodcquinoline ethiodide wererefluxed with parts of absolute ethyl alcohol and 2.1 parts oftriethylamine for about fifteen minutes. The dye separated from thecooled solution. It was filtered ofl and recrystallized from glacialacetic acid, yielding red crystals with a green reflex.

EXAMPLE 3.-,-5- (1 -ethyl-Z-quinolylidene) -2,4,6-

triketohexahydropurimidine 86 2.6 parts of barbituriacid and 8.2 partsof Z-iodoquinoline ethiodide were refluxed with 200 parts of absoluteethyl alcohol and 4.24'p'arts of triethylamine for about fifteenminutes. The

dye was filtered from the cooled solution. It was 40 recrystallized frommethyl alcohol, yielding yellow crystals.

EXAMPLE 4.-5-(l-ethyl-z-quinolylidene)-2-thio-2,4,6-triketohezahydromlrimidine 1.4 parts of thiobarbituric acid and4.1 parts of 2-iodoquinoline ethiodide were refluxed with 80 parts ofabsolute ethyl alcohol and 2.1 parts of triethylamine for about twentyminutes. The

dye was recrystallized from water yielding orange colored crystals.

- Exaupne 5.-5-(1-ethul-z-mridulidene)-3- phenulrhodanine 2.1 parts ofof 2-iodopyridine ethiodide were refluxed with 2.12'parts oftriethylamine and 30 parts of absolute ethyl alcohol for about fifteenminutes. The dye was filtered from the cooled solution. It wasrecrystallized from methyl alcohol, giving reddish-brown plates whichgave ayellow-orange solution in methyl alcohol.

Emma 6.5- (I-ethyl-z-p naphthoquinolyti- Iv dene)-3 -phenylrhodanine 0.3part of.3-ph'eny1rhodanine and 0.66 part of 2-iodo-p-naphthoquinolineethiodide. were refluxed with 0.& part of triethylamine and 15 The dyewasfiltered from the cooled solution.

It was recrystallized from glac al a fit c 8 giving brick red crystalswhich gave a red solution in methyl alcohol. p-naphthoquinoline is alsocalled 5,6-'benzoquinoline. a

3-phenylrhodanine and 3.6 parts 55 a Exmna 7.--(1-ethyl-2-quinolylidene)rhodanine 0.44 g. (1 mol.) ofrhodanine, 1.3 g. (1 mol.) of

Z-phenylthioquinoline ethiodide and 0.36 g. (1.05

mol.) of triethyla nine were refluxed in cc. of absolute'ethyl alcoholfor fifteen minutes." Theydye separated from the chilledsolution. Yield69%. Following recrystallization =trom' glacial acetic acid, the dye wasobtained in the form of redcrystals -with a green reflex. Yield 52%. 2-(ll-11111737101110) I 2-(p-tolylthio) 2-(pnaphthy1thi0)- '6?"2-(1-benzothlazolylthioquinoline non.

can also be condensed with rhodanin'e' to yield :thesame merocyanine.

mma 8.3-eth1lt-5- (I-ethyl-Z-quinolylidefie) .rhodanine 0.32 g (1 mol.)0! 3 ethy1rhodanine. 0.8 g.'(1

utes. The dye separated from the chilled soluas red crystals. Yieldphenyl-rhodanine a 0.52 g. (1v mol.) '01"--3- pheriylrhodanine, 1.0g; (1mol.) of 2-phenylthioquinoline ethiodide and i 0.26 g. 1.05 mol.) oftriethylaniine were refluxed in 151cc. o1 absolute ethyl ,alcohol"forflftee'n minutes.

of the dye from glacialacetic acid, the dye was obtained as brownish'redcrystals :with green reflex. Yield-06%. v

By employing 2-phenylthiopyridine 'ethiodide With-:3-phenylrh0danine, 5-('1-ethyl-2-pyridy1idene).-3;phenylrhodanine is obtained in the, form i-b als u n r stallizatlon or read sh town cryst p0 ecry from pyridine.(25 cc. per gramof dye); the dye from. methyl alcohol.

dene) -1 -phenyl-z-thiohydantoin 1.1 g. (1 mol.) of 3-ethyll-phenyl-Z-thiohydantoin, 2.0 g.- (1 mol.) of 2-phenylthioquinolineethiodide and 0.53 g. (1.05 mol.) of trlethylamine wererefluxed forfifteen minutes in 20 cc. of

absolute ethyl alcohol. The dye separated from the ch lled sdlution. .Yeld 73%. Following recrystallization from methyl alcohol (365 cc. per

gram of dye), the dye was obtained as dark greenish crystals. v 4

The 3-ethy1 1 -phenyl-2 thiohydantoin used in thispreparationwasprepared by heating 17.0

g. (1 incl.) 01' phenyl glycine ethyl ester and 8.7

g. (1- mol.) of ethyl isothiocyanate in an open flask on the steam bathfor 48 hours. The heavy viscous syrup so obtained wasdiluted with methylalcohol, precipitat ng the compound. Yield 63%.

Following recrystallization from methyl alcohol 0.7 g. (1 mol.) of3-ethyl-2-thio-2,4(3,5) -oxa-'. 1 zoledione, 2.0 g. (1 mol.) ofZ-phenylthioquino- 1 line ethiodide and 0.53 g. (1.05 mol.) oftriethylamine were refluxed in 20 cc'. .of absolute ethyl j alcohol forfifteen minutes. The dyeseparated from the chilled solution. Yield 63%.Following recrystallization from-methyl alcohol (300 cc. per

obtained as orange;

gram of dye), the dyewas prisms. Yield 58%.

.Yield '69%-.'-- Following recrystallization from glacial aceticacid','the dye was obtained r The dye separated tromthe chilledsolution. Yield 88%; Following recrystallization Exmus12.-5-(Z-dhvl-I-benzothiazylidene) 1 rhodanine 1.1 g. (1 mol.) ofl-methylthlobenzothiazole, ethiodide, 0.44 g. (1 mol.) oi! rhodanine and0.35 g. (1.05 mol.) of triethylamine were refluxed in 20 cc. of absoluteethyl alcohol for fifteen minutes. The dye separated from-the chilled.solu-. tion. Yield Following recrystallization from pyridine (30 cc.per gramo'f dye), the dye -was obtained as brightyellow powder. Yield45%.

The l-methylthiobenzothiazole ethiodide used in this preparation wasmade by heating 1-meth-.

ylth obenzothiazole-.(20 g.; lmol.) and ethylsiodide.-(21.7 g.; 1.25mol.) for 48 hours on the steam bath; The yield was 31%. Y

The l-methyithiobenzothiazole used above was prepared by treatingI-mercaptobenzothiazole droxlde (5'1 g.;-1.-5 mol.). Yield 92%.Following -,dlstillation the l-methylthiobnzothiazole was obtained as aclear liquid. Yield 1-'me thylthiobenzoxazole andjits ethiodide, as wellas l-phenylthiobenzothia'zole, l phenylthio ben zoxazole. 1- (nbutylthio).ebenzothiazble, 1- (n-- butylthio) -ben zoxazjole, 1-(p-naphthylthio) -ben- -zothiazole and 1- s-naphthylthio)' benzoxazoleand their ethiodides can be made in the same manner. Theseethiodidescanall be condensed with. rhodanines, hydantoins',f2,4(3',5)oxazolediones and the like. 4mm13.--3-ethyl=5-(z-ethbz-Lbeneotniazyzidene) -rhodanine 0.53 g. (1 mol.)of 3-ethylrhodanine, 1.1 g.;(1 mol.) of l-methylth ob'enzothiazoleethiodideand 0.35'g. (1.05 mol.) of triethylamlne'were refluxed in 15cc. of absolute ethyl alcohol for fifteen minutes. The dye separatedfrom the chilled solution. Yleld93%. Following recrystallization Y (50g.; 1 mol.) with dimethyl sulfate (57 g.; 1.5 mol.) in the presence ofaqueous sodium hywas obtained as yellow crystals with a, blue reflex. 5

Yield 75%. 1 EXAMPLE l4.-5-(2-'eth1 l-1.-benzothiazylidene) -3-phenyl-rhodanine' "0:: g. (1 mol.) of 3- phenylrhodanlne, 1.1 g. (1mol.) of 1-methylthiobenzothiazole ethiodide and 0.35 g. (1.05 mol.) oftriethylamine were refluxed in 15 cc. of ethyl alcohol for fifteenminutes. The

dye separated from the chilled solution. Yield Followingrecrystallization from pyridine (.9000. per gram of dye),.the dye wasobtained as bright yellow crystals.- Yield 73%.

EXAMPLE 15.3-ethl/l-5-(Z-ethyZ-J -benzothiazylidene) -2-thio-2,4(3,5)-oxazoledione 1 crystallization from glacial acetic acid (20 cc.

per gram' of dye), the dye was obtained as pale yellow crystals. Yield55%. EXAMPLE 16. 5-(2 -ethyl-.1,-benzothiazylidene)-1,3-diphenyl-z-thiohydantoin odide and 0.35 g. (1.05 mol.) oftriethylaminewer'e 0.9 g. 1 mol.). oi 1,3-diphenyl 2ethiohydantoin, '1.1g.- 1 mol.) of 1-methylthiobenzothiazole ethi refluxed in 15 cc. ofabsolute ethyl alcohol for fiIteen minutes.- The dye; separated from thechilled solution. Yield 77%. Following recrystallization from glacialacetic acid (35 cc. per gram of dye), the dye was obtained as dullyellow crystals. Yield 40%.

EXAMPLE 17.--1 (2 ethyl-1-benzothiazylidene) 2(1) -thionaphthenone 0.5g. (1 mol.) of 2(1)-thionaphthenone, 1.1 g. (1 mol.) ofl-methylthiobenzothiazole ethiodide and 0.35 g. (1.05 mol.) oftrlethylamine were refluxed in cc. of absolute ethyl alcohol for fifteenminutes. The dye separated from the chilled solution. Yield 80%.Following recrystallization from glacial acetic acid cc. per gram ofdye), the dye was obtained as yellow crystals. Yield 60%.

EXAMPLE 18--5-( 2 -ethyZ-1 -benzothiaxylidene) -2- diphenylamz'no-4 (5)-thiazolone 0.45 g. (1 mol.) of 2-diphenylamino-4(5) -thiazolone, 0.56g. (1 mol.) of l-methylthiabenzothiazole ethiodide and 0.18 g. (1.05mol.) of absolute ethyl alcohol were refluxed in absolute ethyl alcohol(15 cc.) for fifteen minutes. The dye separated from the chilledsolution; The yield of crude dye was from glacial acetic acid cc. pergram of dye), the dye was obtained as a pale yellow powder. Yield 23%.

EXAMPLE 19.--3 ethyl-5-(2 ethyl-1 -benzo:razylabout 0C.. for about 12hours.

idene) -rhodam'ne 1.61 g. (1 mol.) of 3-ethylrhodanine, 3.22 (1 mol.) ofl-methylthiobenzoxazole ethiodide and 1.06 g. (1.05 mol.) oftriethylamine were'refluxed for fifteen minutes in 35 cc. of absoluteethyl alcohol. The dye separated from the chilled solutions Yield 50%.

crystals. Yield 35%.

The l-methylthiobenzoxazole ethiodide used in this preparation was madeaccording to the process given in Example 12 forl-methylthiobenzothiazole ethiodide.

EXAMPLE 20.- (Z-ethyl 1 benzothiazylidene) benzoylacetonitrile 0.24 g.(1 mol.) of benzoylacetonitrile, 0.56 g. (1 mol.) of1methylthiobenzothiazole ethiodide and'0.18 g. (1.05 mol.) oftriethylamine were refiuxed in .15 cc. of absolute ethyl alcohol forfifteen minutes. The dye separated from the chilled solution. YieldFollowing recrystaliization from glacial acetic acid'(25 cc. per gram ofdye), the dye was obtained as a colorless compound.

EXAMPLE 21.-3-ethyl-5-(2-ethyl 1 benzothiazylz'dene) -rhodam'ne 0.81 g.(1 mol.) of 3-ethylrhodanine, 2.0 g. (1

mol.) of 1-phenylmercaptobenzothiazole ethiodide, 0.5 g. (1 mol.) oftriethylamine and 50 cc. of absolute ethyl alcohol were refluxed about10 minutes. The reaction mixture was chilled at The yellow solid whichseparated was filtered oil and washed with methyl alcohol. After tworecrystallizations from pyridine the dye melted'at 246 to 247 C. Thissame dye was prepared exactly as above, employ- 'ing instead of 2.0 g.of l-phenylmercaptobenzothiazole ethiodide, an equivalent molecularproportion of .l-phenoxybenzothiazole ethiodide. Equivalent molecularproportions of l-(mtoloxy) ,-benzothiazole ethiodide or 1-(oz-naphthoxy)-benzothiazole ethiodide orl-(p-naphthoxy)-benzothiza.zole ethiodide likewise can be Followingrecrystallization The dye was-recrystallizedfrom glacial acetic acid andobtained as yellow the dye exactly as benzene and naphthalene series, i.e. those containing an arylmercaptogroup containing from 'siX to tennuclear carbon atoms, are advantageously employed. Alkylmercaptocyclammonium quaternary salts can also be prepared from mercaptoheterocyclic nitrogen bases, e. g. l-mercaptobenzothiazole, byalkylation, followed by conversion of the alkylated compound with anester, such as an alkyl iodide or alkyl-p-toluenesulfonate, to form thequaternary salt. This latter method is well known in the art.

Substituted-mercapto and aryloxy derivatives of cyclammonium quaternarysalts can be prepared by reacting halogen-substituted heterocyclicnitrogen bases with mercaptans or phenols and then reacting theresulting bases with an ester, such as an alkyl iodide oralkyl-p-toluenesulfonate, for example, to form the quaternary salt.The'following examples serve to illustrate the process:

Examtr: 22.- 2-benzylmercaptoduinoline 16.4 g. (1 mol.) of2-chloroquinoline, 25 g. 2

mol.) of benzylmercaptan and 13 g. (2 mol.) of

% potassium hydroxide were heated about 16 hours on a steam pot. Fromthe brownish viscous liquid which formed, a white solid slowlyseparated. 200 cc. of a 5% aqueous solution of sodium hydroxide wereadded and the resulting mixture agitated until the potassium 'chloridewhich formed was completely dissolved. A heavy oil separated. This oilwas taken up in diethyl ether, the ether -solution dried over anhydrouspotassium carbonate and finally distilled away. The pink residue wasdistilled under sub-atmospheric pressure yielding2-benzylmercaptoquinoline boiling at 220 to 225 C. at 9 mm. of mercurypressure. It solidified upon cooling. After twice recrystallizing frommethyl alcohol, it was obtainedsas almost colorless crystals melting at46 to 47 C.

EXAMPLE 23.2-benzylmercaptoqui1ioline methop-toluenesulfonate 12.5 g. (1mol.) of 2-benzylmercaptoquinoline and 13.5 g. (1.5 mol.)of'methyl-p-toluenesulfonate were heated at about C. for about 96 hours.The brown semi-crystalline mass which formed was stirred with about 25cc. of diethyl ether and then with about 20 do. of acetoneto removeimpurities. The resulting dried crystals were twice recrystallized frommethyl alcohol and obtained as colorless crystals melting at 202 to 204C. with decomposition. This quaternary salt can be employed in myprocess for making merocyanine dyes by reacting with rhodanines, e. g.3-phenyl-rhodanine, or other heterocyclic organic compounds containing anuclear reactive methylene group adjacent to a nuclear carbonyl group. I

' l with 850 cc. of diethyl ether.

Exmns 24.-1-Phenulmercaptobenzothiazole 88.0 g. (2 mol.) of thiophenoland 80.8 g. (2

mol.) oi triethylamine were added alternately.

and under reflux, in small portions and with agitation,. to-67.8 g. (1mol.) o1'1-chlorobenzothia zole warmed to 40 to 50 C. The resultingreaction mixture was heated at about 95 C. for about 211 hours. Uponcooling, 300 cc. of cold ,10. water and then 250 cc. of an aqueoussolution of sodium hydroxide (prepared by diluting 56 cc'. of-

a 40% aqueous solution of sodium-hydroxide with water) were added.='l'he'l-phenylmercaptobemzothiazole was extracted from the watermixture The ether extract was washed with coldwater and dried overanhydrous calcium chloride. The ether was distilled away. The residueupon distillation yieldt ed 1-phenylmercaptobenzothiazole as a slightly.

20 ly yellowish liquid boiling at 183 to 3 mm. or mercury pressure.

EXAMPLE. 25. 1-Phenylmercaptobenzothiaz ole ethiodide 36.5 g. (1. mol.)1 of l-phenylmercapto'benzo thiazole and 34.1 g. (1.5 mol.) of ethyliodide were heated in a sealed-tube at about 100 C. for about 88 hours.The dark tarry mass of crystals'which formed was removed from the tubeand stirred with diethyl ether until; completely crystalline.

. The resulting brown crystals were stirred with acetone untilvcolorless. After recrystallization vfrom nitromethane, the ethiodide wasobtained 15 .as pale yellow crystals melting'at 166 to 167 C. I

This quaternary salt can-be employed in myprocesstonmakinrmerocyanine-dyes byyreacting' with rhodanines, e. g.3-ethylrh6danine, or other heterocycllc organic compounds containing anuclear reactive methylene group adjacent to a nu- 40 clear carbonylgroup.

EXAMPLE 26.4- Phenylmercaptopyridine' 15.5 g. (1 mol.) of4-chloropyridine were added to 22 g. (1 mol.) of thiophenol cooled in afreez- 45 ing mixture. A vigorous reaction took place and the reactionmass set to a solid. The solid reaction mass vwas then heated atabout100 C. for about minutes. The solid so obtained was .the hydrochlorideoi 4'-phenylmercaptopyridine.' It

I 50 was washedwith diethyl etherand i-phenylmei captopyridine generatedtherefrom by treatment with aqueous ammonia,- The free base was taken upfrom the ammonia reaction mixture with (11- ethyl ether- Thediethylether was distilled away.

6 Upon distillation 'of the residue, 4-phenylmer captopy'ridlne wasobtained as a colorless liquid boiling at 128 to 129 C. at 2 mm.ofwmercury pressure. 1

. 0'0 Exnrrm; 27.4-Phenulmercaptopuridi ne metlii odtde 3.4g. (1 mol.)of 4-phenylmercaptopyridine and 6.6 g. .(2 'mol.) of methyl iodldeweregently 65 refluxed for about .30 rninutea The initial reactionwas-vigorous. The methiodide separated from the; cooledreaction mixture.It was washed with, diethyl ether and dried in vacuo. It was in theform. of colorless crystals melting at 174 to 7o 176 C. withdecoinpositiom This quaternary saltcan be employed in my process to makemerocyanine dyes by reacting with rhodanines. e. g. 3-.

.ethylrl odanine, or other heterocyclic organic compounds containing areactive nuclear meth 1| ylene group adjacent .to a nuclearcarbonylgroup.

,adjacentto a nuclear carbonyl group.

I have found that simple merocyanine dyes Exmui28.1-phenorybenzothiazole added through the condenser and the mixtureshaken to dissolve the potassium chloride. Upon cooling a brownish oil'separated. Thisoil was taken up in diethylether and the ether-solutiondried over anhydrous potassium hydroxide. The ether was distilled away.The residue upon distillation yielded l-phenoxybenzothiazole as a nearlycolorless liquidboiling at 166 to 170 C.

. at 2 mm. of mercury pressure. Upon cooling the liquid solidified tocolorless crystals melting at 50 to 52C. l-(m-toloxy)-benzothiazoleprepared from m-cresol was obtained as colorless crystals melting at 66to 68 C.

Examraa 29.--1-phenoxybenzoihiaeole et hiod ide" 11.4 g. .(llnoL) ofl-phenoxybenzothiazole and 12 g. (1.5 mol.) of ethyl iodide were heatedin a sealed tubeat 100 C. for about-88 hours. The

tarry brown' viscous mass formed was ground with absolute diethyl etheruntilcrystalllne. The a brown crystals were crushed in acetone 'untilnearly colorless. Upon recrystallization from nitromethane, theethiodide' was obtained as nearly colorless crystals melting at 187 to189 C. This quaternary saltca'n be. employed inp'my process for makingmerocyanine dyes by react- .vingwith vrhodaniries, e. g.3-phenylrhodanines, .or' other heterocyclic organic compounds containinga nuclear reactive methylene group adjacent to a nuclear carbonyl group.

" ExAMPL'E ;-1-( -naphthoxy benzothiazole- 17 g." (1 mol.) ofl-chlorobenzothiazole and. 28.8

g. (2- mol.) of a-naphthol were treated as in Example 28. 1-(a-naphthoxy) -benzothiazole was obtained as a slightly yellowish oilboiling at 225 to 235 C. at 3 mm. of mercury pressure. Upon cooling, theoil solidified and upon recrystalliza-' 'tion of the crystals frommethyl alcohol, colorless crystals melting at 88" to90 C. were obtained.Obtained in the same manner l-(p I naphthoxy) -benzothiazole melted at62 to 65 C. "EXAMPLE 31. --1-(u -naphthoxy) benzothiazole ethiodide 6.9g. (1 mol.) '01" l-(a-naphthoxy) -benzothiazole and 6 g. (1.5 mol.) ofethyl iodide were' heated in a sealed tube at about 100 C. for about..48 hours. Upon recrystalliaing the-reaction mass from. nitromethane,the ethiodide was obtained as nearly colorless crystals melting at 188to .190 C. This quaternary salt can be employed to prepare merocyaninedyes by'my process by reacting with"-arhodanine','je.' g. 3-phenylrhod'anlne, or another heterocyclic organic compound;

containing a nuclear reactive methylene group containing a quinolinenucleus linkedthrough its 4-position can advantageously beprepared froma quinoline quaternary salt and a heterocyclic organic compoundcontaining a nuclear reactive methylene group adjacent to a nuclearcarbonyl group, particularly rhodanines. The

. reactions are advantageously conducted in the presence of a basiccondensing agent, and diluent, such as the basic condensing agents anddiluents set forth above. The following examples will serve toillustrate my new process.

Emu 32.-(1 ethyl-4-quin0lylidcne)- rhodanine 1.33 g. (1 mol.) ofrhodanine, 5.7 g. (2 mol.) of quinoline ethiodide, 50 cc.- of absoluteethyl a1- cohol and 1.4 g. (2 mol.) of potassium hydroxide (85%) wererefluxed for about minutes. The dye separated from thecooled reactionmixture. It was recrystallized from glacial acetic acid and obtained asbeautiful wine-red crystals having a blue reflex. Its methyl alcoholicsolution was pinkish-red. It melted at 285 to 287 C. with decomposition.

EXAMPLE 33.-3-eth/yl-5-(1-ethyl-4-quinolylidene) ,-rhodum'ne 1.61 g. (1mol.) of 3-ethy1rhodanine, 5.7 g. (2

mol.) of quinoline ethiodide, cc. of absolute ethyl alcohol and 1.4 g.(2 mol.) of potassium hydroxide were] refluxed for about 10 minutes. Thedye separated from the cooled reaction mixture. It was recrystallizedfrom glacial acetic acid and obtained as red needles having a bluishreflex. Its methyl alcoholic solution was pinkish-red. It melted at 204to 206 C. with decomposition.

Exmu: 34.5 -(1-ethyl-4-quinolylidene) -3- phenylrhodanine 2.11 g. (1mol.) of 3-phenylrhodanine, 5.7 g. (2 mol.) of quinoline ethiodide, 50cc. of absolute ethyl alcohol and 1.4 g. (2 mol.) of potassium hydroxide(8.5%) were refluxed for about 10 minutes. The dye separated fromthecooled reaction mixture. It was recrystallized from glacial aceticacid and obtained as red needles. It

-melted at 281 to. 282, C. with decomposition.

Itsmethyl alcoholic solution was pinkish-red.

Exammr. 35.3-eth1 l-(1,6-dimethyl-4-quinolyli-- dene) -rhodanine 1.61 g.(1 mol.) of- 3-ethylrhodanine, 5.7 g. (2

mol.) of fi-methylquinoline methiodide, 50 cc. of absolute ethyl alcoholand 1.4 g. (2 mol.) of potassium hydroxide (85%) were refluxed for about10 minutes. The dye'separated from the cooled reaction mixture. It wasrecrystallized from glacial acetic acid and obtained as reddish needleshaving a blue reflex Its methyl alcoholic solution was pinkish-red.

As illustrated in-the above four examples,'I have found it advantageousto employ an excess of both the-quinoline quaternary salt and the basiccondensingagent in order to obtain higher yields of dye. percent excessof each is suitable.

My merocyanine dyes can be employed to manufacture optically sensitizedgelatiho-silverhalide, particularly gelatino-sllver-chloride emul--sions. My merocyanine dyes can also be employed in manufacturing lightfilters and in the dyeingof cellulose acetate textile yarn The dyescontaining a barbituric acid nucleus of thiobarbituric acid nucleusareparticularly useful in cellulose acetate textile dyeing.

What I claim and desire to be secured by Llet-- ters' Patent of theUnited States is:

1. A merocyanine dye characterized by the following formula:

,2. r. ""A=b -c'=b-1-i-n wherein A representsa divalent atom. selectedfrom the group consisting of oxygen and sulfur,

R represents an-alkyl group, Y represents the non-metallic atomsnecessary to complete avheterocyclic nucleus selected from the groupconsisting of azole, azoline, indolenine, py dine and quinoline nucleiand Z represents the non-' metallic atoms necessary to complete aheterosisting of azole, azoline, indolenine, pyridine and quinolinenuclei and Z represents the non-metallic atoms necessary to complete aheterocyclic nucleus selected from the group consisting of five-;memberedheterocyclic nuclei containing a nuclear sulfuratom,flve-membered heterocyclic nuclei containing a nuclear nitrogen atom andsix-memberedheterocyclic nuclei containing a nuclear nitrogen atom. 1

by one wherein A represents a divalent. atom selected from the groupconsisting of oxygen and sulfur atoms, R represents an alkyl group, Yrepresents wherein R represents an alkyl group, Y represents thenon-metallic atoms necessary to complete aheterocyclic nucleus selectedfrom the group con- I the non-metallic atoms necessary to complete a- 'fheterocyclic nucleus selected f m the group consisting of azole,azoline, indole e, pyridine and quinoline nuclei, Y represents thenon-metallic atoms necessary to complete a heterocyclic nucleus selectedfrom the group consisting of pyridine and quinoline nuclei and Zrepresents the non-metallic atoms necessary to complete a heterocyclicnucleus selected from the group consisting of flve-membered heterocyclicnuclei containing a nuclear sulfur atom, five-membered heterocyclicnuclei containing a nuclear nitrogen atom and six-membered heterocyclicnuclei com taining a nuclear nitrogen atom.

4. A merocyanine dye characterized by. the following formula:

wherein R represents an alkyl group, Y represents the non-metallic atomsnecessary to complete a .heterocyclic nucleus selected from the groupconsisting of azole, azoline, indolenine,'pyridine, and

quinoline nucleus and'Z represents the nonmetallic atoms necessarytocomplete a flve-' membered heterocyclic nucleus containing a nuclearsulfur atom. I v y g 5. A merocyanine dye characterized by the followingformula:

- wherein R represents an alkyl group, Y representsthenon-metallicatoms. necessary to complete a quinoline nucleus and Zrepresents the nonmetallic atoms necessary to complete a rhodaninenucleus. i 6. A 5-(1-alkyl-2-quinolylidene) -rhodanine.

v of the benzene and naphthalene series with a 7. 5(1-ethy1-2-quinolylidene) -rhodanine. 8. A merocyanine dye lowingformula:

' ,z. o=b0'=b-1-i-R wherein R represents an alkyl group, Y representsthe non-metallic atoms necessary to complete a quinoline nucleug and Zrepresents the nonmetallic atoms necessary to, complete a 2-thio- 2,4,6triketohexahydropyrimidine, nucleus. 9. A5-!1-alkyl-2-quinolylidene)-2rthio-2,4,6-

triketohex'ahydropyrimidine.

10. 5-(1-e'thy1 2 quinolylidene) -2-thio-2,4,6-triketohexahydropyrimidine.

11. 5 -(1 ethyl 2 pyridylidene) 3 phenyl rhodanine.

. 12. A merocyanine dye characterized by the following'formula; v V

z. o='co'=b'-Na wherein It represents an alkyl group, Y represents thenon-metallic atoms necessary to complete a quinoline nucleus and Zrepresents the non- 'metallic atoms necessary to complete a livememberedheterocyclic nucleus containing a nuclear'suliur atom.

13. A process for preparing a merocyanine dye comprisingreacting, in thepresence of a basic condensing agent, a cyclammonium quaternary saltcontaining, in. a reactive position, a reactivegroup selected from thegroup consisting of halogen atoms, arylmercapto groups of the benacneand naphthalene series and aryloxy groups 'otthe benzene and naphthaleneseries, witha heterocyclic organic compound containing a nuclearreactive methylene group adjacent to a nuclear'carbonyl group.-

14. A process for preparing amerocyanine dye comprising reacting, in"the. presence of a basic oonclensing'agent, a cyclammonium quaternarysalt containng, in a reactive position, a reactive 7 group selected fromthe. group consisting of halogen atoms, arylmercapto'groups of thebenacne and naphthalene series and .aryloxy groups heterocyclic .organiccompound containing a nuclear reactive methylene group adjacent toacharacterized 'by the fol-.

nuclear carbonyl group and selectedirom thegroup consisting offlve-membered and six-membered heterocyclic organic compounds.

; consisting of halogen atoms, arylmercapto groups 7 15. A process forpreparing a merocyaninedye comprising reacting, in the presnceoi anorganic base having a dissociation constant substantially tion, areactive group selected from the group greater than that of pyridine, acyclammonium quarternary 'salt containing, in a reactive pos i-- of thebenzene and naphthalene series and aryloxy groups of the benzene andnaphthalene series,

.with' a heterocyclic compound containing a nuclear reactive methylenegroup adjacent to a nuclear carbonylgroupand selected from the groupconsisting of flve-membered and six-membered heterocyclic organiccompounds.

.16. A process for preparing a merocyaninedye comprising reacting,- inthe presence or a tertiary organic base having a dissociation constantsubstantially greater than that of pyridine, acyclam- -monium quaternarysalt containing, in a reactive position, a reactive group selectediromthe group consisting of halogen atoms, arylmercapto groups of the;benzene and naphthalene seriesand aryloxy groupsof the benzene andnaphthalene series,

- with a heterocyclic compound containing a nuclear reactive methylenegroup adjacent to a nuclear carbonyl group and selected from the groupconsisting of flve-membered and six-membered heterocyclic organiccompounds.

17. A process. for preparing a merocyanine dye comprising reacting, inthe presence of a basic condensing agent, a cyclammonium alkiodidecontaining, in a reactive position, an iodine atom reactive methylenegroup adjacent to a nuclear carbonyl group and selected from the groupcon sisting of flve-membered and six-membered heterocyclic organiccompounds.

19. A process for preparing a'merocyanine dye comprising reacting,.inthe presence of a basic condensing agent, a 2iodoquinoline alkiodide,with a heterocyclic organic compound containing a nuclear methylenegroup adjacent to a nuclear reactive carbonyl groupand selected from thegroup of five-membered' and six-membered heterocyclic organic compounds.

' 20. A process for preparing a merocya'nine dye comprising reacting, inthe presence of a basic condensing, agent, a 2-iodoquinoline 'alkiodfdewith 'a'rhodanine.

- 21. A process'tor preparing a merocyanine dye comprising'reacting, inthe presence of a tertiary organic-base having a dissociation constantsubstantially greater than pyridine, a 2-iodoquinoline :alkiodide witha. rhodanine.

LESLIE G. s.

CERTIFICATE OF CORRECTION. I Patent, No. 2,185,182. I January 2, 1 91 0.

LESLIE G. s. I BROOKER.

It is hereby certified that error appears in the printed specificationofthe above numbered patent requiring correction as follows: Page 2, firstcolumn, line 1h, for the word "reaching" read -reacting--; page 7 sec-0nd column, line L T, claim l9, strike out'the word "reactive" andinsert the same before "methylene" i line 1 6, same claim; and thatthe'said Let- 'ters Patentshould be read with this correction thereinthat the same may conform to the record of the case in the PatentOffice. Signed and sealed this 7th day of May, A. D. 191,0.

, v Henr Van Arsdale, (Seal) Acting Connn issioner of Patents.

